Ignition timer



Oct. 29, 1929.

W. A. CHRYST IGNITION TIMER Filed Jan. 13. 1928 Patented Oct. 29, 1929UNITED STATS Panam?v OFFICE WILLIAM A. CHRYST, F DAYTON, OHIO, ASSIGNORTO DELCO-REMY CORPORATION,

' OF DAYTON, OHIO, A CORPORATION OF DELAWARE IGNITION TIMER Applicationled January 13, 1928. Serial No. 246,637.

This invention relates to ignition apparatus for internal combustionengines, and more particularly to the control of ignition timing inresponse to variations in engine speed and to variations in engine load.

One object of the present invention is to provide for the control ofignition timing by means cooperating with an annular piston slidingwithin an annular cylinder provided by the timer housing and locatedconcentric with the axis of the timer driving shaft, the piston andcylinder cooperating to provide a suction chamber which is connectedwith the engine intake passage. In carrying out this obj ect of theinvention, I provide a cam carrying shaft which is journalled upon aportion of the timer driving ,shaft so that it may be rotated relativethereto, and I connect the vshafts by a mechanism which can be confinedwithin the timer housing and which is con'- trolled by the suctionoperated piston referred to. A collar which is connected with the pistonand moves axially of the two shafts is so connected with them as to varythe angular l relation between these shafts in `response to movements ofthe piston.

Further objects and advantages of the present invention will be apparentfrom the following description, reference bein had to the accompanyingdrawings, wherein a preferred form of embodiment of the presentinvention is `clearly shown. In the drawings: .t Y

Fig. 1 is in part a vertical sectional view of an ignition timerembodying the present invention and in part a diagram showing the mannerof connecting the suction chamber of the ignition timer with the engineintake passage. U

Fig. 2 is a plan view of the timer with the distributor head removed,and is a view on the plane of the line 2-2 of Figfl..

Fig. 3 is a fragmentary sectional view lookin in the direction of thearrow 3 of Fig. 1. Fig. 4 is a view similar to Fig. 1 showing certainparts in other operating positions.

Fig. 5' is a sectional view on the l1ne ,5 5 of Fig. 1.

In the drawings, 20 designates the housing of the timer whlch supports aconventional socket 22 having a contact 23'for en aging a contact 24supported by a rotor connected with the contact 24 and rotated adjacentto a plurality of distributor'posts whichfare arranged in af circularrow. One of these posts is shown at 27 and is integral with a socket 28for receiving a plug or terminal connector (not shown) attached to awire leading to an engine spark plug.

The rotor block is supported by and driven by a cam carrying 'shaft 30which rotates loosely about an extension 31 of a timer driv. ing shaft32 which is supported by a bearing provided by the tubular shank 33 ofthe timer housing. The shaft '30 is provided with a cam 34 whichco-operates with a rubbing block 35 of a circuit breaker lever 36carrying a contact 37 adapted to engage a stationary contact 38supported by an adjustable bracket 39 which is adjustable about thepivot stud 40 of the lever 36. A leaf spring 41 conducts current from aterminal 42 to the lever 36 and urges the contact 37 toward the contact38 and the rubbing block 35 toward the cam 34. The lever 36, bracket 39and terminal 42 are supported by a plate 43 having ears 44 by which thelate may be attached to the timer housing y screws 45. The terminalbracket 42 is insulatingly supported by the plate 43 and is connectedwith a terminal screw 46 which is insulated from the housing. Acondenser which is contained within a case 47 is attached by clip 48 andscrew 49 -to the plate 43. One

-of the con denser foils is electrically; connected with the condensercase 47 and hence with the plate-43, and the other foil is connectedwith the terminal bracket 42 by a conductor 50.

The lower end of the cam carrying shaft 30 rests upon a shoulder 5'1provided by the shaft 32 and is attached to afplate providing arms 52each of which is adaptedto cooperate with an arm 53 of a weight 54. Eachweight 54 is supported by weight plate 55 and swings around a stud 56attached to the plate 55. A spring 57 connects a stud 58 carried by anarm 52 -with one of the studs 56 and in this way tends to move the plate54 toward the shaft 32. .The plate 55 is attached to and is t lock 25 vcarrylng a distributor segment 26 electrically i Awhich is supported bya vdiagrammatically by a carburetor 61 and an intake manifold 62.- Thethrottle 63 of the carburetor 61 is operated by Aa lever- 64 and a rod65. The carburetor is provided with a passage 66 which is anterior tothe throttle when closed and which is on the engine side of the throttlewhen thev throttle is opened a substantial'amount. The passage 66 iscon# nected by a pipe 67 with an elbow 68 screwed into the timer housing20 and communicates with an annular cylinder or suction chamber 70having a movable wall provided bypiston 71 which slides along an annularboss 72 pro- 'viding a part of the bearing for the shaft 78 res spectivey space between the flanges l 32. The cylindrical surfaces defining theannular cylinder 7 0 are en piston packing'member 3 which is attached lrivets 74 .to the piston, andl these rivets 74 g a so secure tothepiston the flanges and 76 of two nested cup-shaped tivelyv which' are`located concentric with t e shaft 32 and which are provided withinwardl `extending flanges .79 'and 80 y relocated m spaced relation.lThe 79` andl 80 is'occupied by a disc or` collar 86, the ,thickness of,which is slightly less than the distance between the flanges 79 and 80so that the collar aged by an annular- 86 is Vfree to 'rotate relativeto the piston 71.v

. The collar 86 isprovided with inwardl tending lugs 8 whichy are-receive by longitudinally extending grooves 88 provided in the shaft32. and oblique slots 89 in the intermediate shaft 59. Normally'a spring90 urges the piston 71 upwardlyI until the flange 476 of the part 78strikes an annularplate 91 attached b screws 92 to the housing 20.

The sha 32 is driven by the engine in the usual manner and `drives theintermediatel shaft 59 throughthe lugs 87 of the collar 86. Theintermediate shaft 594drives thecam 3 4 through the cooperating weights54 and lever ,arms 5 2. As the speed of the shaftincreases,

the weights 54 move outwardly due `to centrifl force and move the camclockwise re ative to the shaft 32 in order to advance the timing'of.the ignition, the normal direction y of rotation' of the' cam 34 beingclockwise.l

In .this vway the spark is advanced auto- P matically as the s d of theen e increases.. While the engine is idling, t e throttle 63 'will beopened only a slight amount and thev passage 66 will be practically cutoff from thev influence of suction in the. intake manifold 62. Thereforethe sprin will befree to maintain the collar 86 in t e position shown in1 and the timing of the ignition will be I wise as cumulativelyanddifferentially. of the engine increases, both devices may act .creasedwhile itsload is bein lopened (to permit the lengine to -increase -its"speed,

the passage ,66 will be placed in comjthe engine intake so that thepressure in the suction chamber 70 will be ysub-atmospheric. l Thereforethe piston 71 will bemoved downwardly to move the collar 86 downwardly.The oblique slots 89 are so constructed rthat downward movement of themunication. with collar 86 will cause the shaft 59 to move clockviewedfronrthe top'of the ignition timer. Therefore, the cam 34 will'berotated clockwise'relative to-the'shaft 32 and the timing of theignition will be advanced.

When the engine load is suddenly increased, Itending to reduceits speed,and the throttle 63 is opened to supply a greater lamount of fuel to theengine, the suction in-.the intake 62 will be reduced; consequently thespring 90 will move the piston 71 upwardly to a position in whichequilibrium is established between the spring pressure and the pressurediferential tending to move the piston down-- wardly. Consequentlythecollar 86 will be moved upwardly a certain amount in order to retardlthe ignition in amount corresponding to the load of the engine.

It is apparent that the speed responsive centrifugal 'device and thesuctionfresponsive device' for controlling the advancing and retardingof vthe timing ignition may operate Asthe speed cumulatively torotatethe cam 34 relative to the shaft'32 in such direction as :toadvance the timingv of the y:ignition and vice versa as the speeddecreases. There may be conditions under which the speed of theengine isin' vThe centrifugal device ma ten to advance the position 'of.thecam-re ative to the drive shaft `While the suction-control device mayaoI increased. v

tend to retard it.. rThus both devices may act diiferentially,-tofcontrol the position of the cam 34 relative tothe drive shaft 32 sothat the ignition'will betimed properl to correspond'with the enginespeed and oad conditions 1 One of theimportant'featuresv ofthepresentinvention is the provision for facilitating therepairs-andreplacements of the devices which control the timing oftheignition.

4The centrifugal device may be'vremoved from' the timer withoutdisturbing the suction responsive device. After removing thedistributor'head 21v andthe timer Supportingl late 43 the assembly ofdistributor rotor 25, cam shaf`t`30, intermediate shaft 59 andcentrifugal deviceconnecting the shafts may be.

removed from the shaft 32 in assembled relation without disturbing theshaft 32 or the collar 86. Incase it is desired to remove the piston 71and parts connected therewith including the collar 86, the screws 92 areremoved 1n order to permit removal of the plate 91. After this has beendone, the piston 71 and the spring 90 may be removed from the cylinder70.

While the form of embodiment of the present invention as hereindisclosed, constitutes a preferred form, it is to be understood thatother forms might be adopted, all coming Within the scope of the claimswhich follow.

What is claimed is as follows 1. Ignition apparatus for internalcombustion engines comprising, in combination. an interrupter, a cam foroperating the interrupter, a drive shaft, a driven shaft connected withthe cam and surrounding the drive shaft, means for connecting the twoshafts and including a collar slidable along the driven shaft and havinga lug extending into a longitudinal slot in one of the shafts and Y intoan oblique slot in the other shaft, and a device for moving the collaralong the shaft in order to change the angular relation between theshafts.

2. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, adrive shaft, a driven shaft connected with the cam and surrounding thedrive shaft, means for connecting the two shafts and including a collarslidable along the driven shaft and having a lug extending into alongitudinal slot in one of the shafts and ito an oblique slot intheother shaft, and a device responsive to variations in engine intakesuction for moving the collar along the shaft in order to change theangular relation between the shafts.

3. Ignition' apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, adrive shaft, a driven'shaft connected with the cam and surrounding thedrive shaft, y

means for connecting the two shafts and including a collar slidablealong the driven shaft and having alu extending into a longitudinal slotin one o the shafts and into an oblique slot in the other shaft. and adevice responsive to variations in engine intake suction for moving thecollar along the shaft in order to change the angular relation betweenthe shafts, said device comprising an annular suction chambersurrounding the drive shaft and having a movable annular wall, andcomprising means for connecting the wall with the collar whilepermitting rotation of the collar.

4. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, adrive shaft, a driven shaft connected with the cam, means for connectingthe shafts comprising a collar movable along the shafts and havinga lugextending into grooves inl the shafts, one of the grooves being obliqueto the axes of the shafts, and means for mov- 'ing the collarin responseto variations in enmsaeaa 3 c of the collar.

5. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, adrive shaft, a cam-carrying shaft and an intermediate shaft journalledupon the drive shaft, means for connecting the intermediate shaft withone of the other shafts and comprising a collar slidable along theshafts so connected and having a lug extending into grooves in theshafts so connected, one of the grooves being oblique to the axes of theshafts,\a device for moving the collar along the shaft, and other meansfor connecting the intermediate shaft with another shaft and for varyingthe anglar relation between them.

6. Ignition appartusl for internal combustion engines comprising, incombination, an interrupter, a cam for operatingthe interrupter,-a driveshaft, a cam-carrying shaft and an intermediate shaft journalled uponlthe drive shaft, means for connecting the intermediate shaft with oneof the other shafts and comprising a collar slidable along the shafts soconnected, and having a lug extending into grooves in the shafts soconnected, one of the grooves being oblique to the axes of the shafts, adevice responsive to `engine suction for moving the collar in order tovary the angular relation between the two shafts, and other means forconnecting the intermediate shaft with another shaft and for varying theangularl relation between them.

7. Ignition apparatus for internal combustion engines comprising, incombination, an

interrupter, a cam for operating the interrupter, a cam-carrying shaft,an intermediate drive shaft, a main drive shaft extending into the othershafts and providing bearings therefor, means for connecting the inter.

mediate shaft with one of the other shafts and including a collarslidable along the shafts so connected and having a lug extending intogrooves in the shafts so connected, one of the grooves being oblique tothe axes of the shafts, a device responsive `to engine intake suctionfor moving the collar in order to change the angular relation betweenthe shafts, and a speed responsive device for connecting theintermediate shaft and another shaft and for varying theangular relationbetween them.

8. Ignition apparatus for internal combustion engines comprising, incombination, an interrupter, a cam for operating the interrupter, acam-carrying shaft, an intermediate drive shaft, a main drive shaftextending into the other shafts and providing bearings therefor, meansfor connecting the vintermediate sha-ft with the drive shaft, andincluding a collar slidable .along the shafts so connected and having alug extending into' grooves in the shafts so connected, one of thegrooves4 -being oblique to the axes of the shafts, a device responsiveto engine intake suction for moving the collar in order to change theangularcrelation between the shafts, and a speed responsive device .forconnecting the intermediate shaft with the-camcarrying shaft and forvarying the angular relation between them. l

ln testimonywhereof I hereto aflix my signature. WILLIAM CHRYST.

